The present invention relates generally to the field of control systems and more particularly to a lighting control system for controlling the operation of electrical lighting devices.
Today, automation systems are being installed in more and more buildings, including both new construction and in structures that are being rebuilt. The incentives for putting automation systems into a building are numerous. High on the list are reduced operating costs, more efficient use of energy, simplified control of building systems, ease of maintenance and of effecting changes to the systems. Facility managers would prefer to install systems that can interoperate among each other. Interoperability is defined by different products, devices and systems for different tasks/applications and developed by different manufacturers that can be linked together to form flexible, functional control networks.
An example of a typical automation system includes lighting controls, HVAC systems, security systems, fire alarm systems and motor drives all possibly provided by different manufacturers. It is desirable if these separate systems can communicate and operate with each other.
Prior art automation systems generally comprised closed proprietary equipment supplied by a single manufacturer. With this type of proprietary system, the installation, servicing and future modifications of the component devices in the system were restricted to a single manufacturer""s product offering and technical capability. In addition, it was very difficult or impossible to integrate new technology developed by other manufacturers. If technology from other manufactures could be integrated, it was usually too costly to consider.
Thus, it is desirable to create an open control system whereby individual components and subsystems share information among one another. A few of the benefits of using an open system include reduced energy costs, increased number of design options for the facility manager, lower design and installation costs since the need for customized hardware and software is greatly reduced and since star configuration point to point wiring is replaced by shared media and lastly, system startup is quicker and simpler.
In addition, expansion and modification of the system in the future is greatly simplified. New products can be introduced without requiring major system redesign or reprogramming.
Prior art control networks typically used a bus topology. A block diagram illustrating an example prior art control network that utilizes a bus topology is shown in FIG. 1. The control network, generally referenced 10, comprises a plurality of sensors and control outputs that are all interconnected using twisted pair wiring, for example. Various sensors, such as dimming sensor 16, switch 18 and occupancy sensor 20, are connected by point to point wiring to a central multiplexer 12. Actuator/control devices, such as dimming control 22, switch control 24 and occupancy control 26 are connected to the main bus 14 via individual point to point wiring. The central multiplexer 12 is connected to the main bus 14 via additional wiring. In such a network, all devices must be connected to the main bus 14 in order to function within the control network 10.
The use of bus topology has the disadvantage of requiring costly, time consuming installations because every device in the network must be connected in xe2x80x98home runxe2x80x99 fashion directly to the main bus 14. Installers are not able to branch or star the wiring where it is convenient and cost effective to do so.
The present invention comprises an electrical control system that includes various electrical devices that have the capability to communicate over a network. The various electrical devices include sensors, transducer functions, switching devices, dimming devices and controlling devices. The devices communicate with one another over a network that may be implemented using one or more different types of media. Media types include, for example, twisted pair, power line carrier, coaxial, optical fiber, RF and infrared. Some of the devices may or may not include an integral power supply. Thus, some devices may depend on other devices to supply them with electrical power.
In addition, the system includes the necessary user interfaces, network management system interfaces and displays to provision, administer, commission, operate and maintain the electrical device network. The system is particularly suited for lighting control and load switching/dimming applications, including but not limited to, providing a means to control the lights and/or other electrical loads within an office, building, room or home by means of motion detection, ambient light sensing, switching functions, dimming functions, temperature sensing functions and humidity sensing functions. Most devices are equipped with a means to put the device in an on, off or auto mode.
The communications network system and the electrical devices that comprise the system operate in an environment such as might be found in an office, school, home, industrial plant or other automated facility. In these types of environments, sensors, switching and dimming control actuators are used for electrical control applications including lighting, energy monitoring and control, end user convenience and HVAC control.
The electrical devices that comprise the control system generally comprises one or more of the following five basic elements: (1) user interface, (2) actuator element, (3) power supply and media connections, (4) communications media and protocol and (5) one or more sensor inputs.
For the control system to function it is not necessary for all five of the above elements be present. A device may operate if connected to elements in other devices which are not part of the system, such as a separate micro PLC type device connected directly to a relay or other switching element which, in turn, is connected to one or more of the sensors within the system. Further, it is intended that many other sensors, other than those disclosed herein, could also work directly with the system of the present invention. Typically, little or no modification is required and the required functional profiles and variables or other application code can be downloaded to the appropriate user interface, actuator element, power supply or sensor inputs.
Additionally, other functions can be performed which include some type of annunciation either by sound (by using a buzzer), by sight (by employing LEDs) or by controlling the lights in the room. For example, if there is a fire and the smoke detector transducer and sensor indicates the fire, a local buzzer could annunciate at the sensor and also cause the lighting control unit to flash lights. Alternatively, it could illuminate specially designed lights fixtures made for this purpose. Also, the lighting system could be controlled through inputs received from a security system which outputs commands so as to put the home or office into a xe2x80x98lived in lookxe2x80x99 mode or other appropriate lighting modes.
The user interface, utilized by a user to configure and maintain the devices situated on the network, is optionally present in the network. The user interface can be a hand held device, laptop, palmtop, desktop or a remote control device. In addition, the user interface can be located locally or remotely and may comprise a computer, a touch screen panel or display, a simple keypad or any other wall, surface, tabletop, cellular or other type device that allows any user to interface with the system to either receive information, to control elements of the system, to perform network management on the system and its devices or to report automatically or upon command.
The user interface provides the home or building owner the ability to establish the configuration of the system and it""s desired performance or potential future performance. The user interface also provides real time control and monitoring in addition to providing unscheduled control and information monitoring functions.
The actuator elements of the system may comprise numerous different types of devices including, but not limited to, switching devices, dimming devices, multiple load controlled devices, single load control devices, devices controlled locally, remote control devices, open air gap switching devices, electronic switching or dimming devices, incandescent lighting control devices, fluorescent lighting control devices, high voltage electronic ballast control devices (including both switching and dimming), low voltage ballast control devices (including both switching and dimming), zero crossing circuitry and switching coordination devices and other relay type or load controlling devices.
The power supply component for some of the devices in the system may include means to operate from 100 to 305 VAC. This type of device supplies an output voltage between 8 and 26 VDC as well as 24 VAC to its own internal circuitry in addition to devices external to it. The means for distributing the electrical power to other devices could be accomplished via any suitable means including twisted pair cabling, electrical power line cables or any other power carrying media.
Another key feature of the system is a communications media and protocol that together form a communications network allowing messages to be communicated (1) between devices within the system and (2) between devices located within the system and devices located external to the system. The messages comprise, among other things, commands for controlling and/or monitoring signals and data. These messages could be tightly coupled, loosely coupled or of a macro broadcast nature. In addition, they may be one way, bi-directional, with established priorities or without. The network communications medium may comprise, for example, twisted pair Category 5 cabling, coaxial cabling, a standard POTS line, power line carrier, optical fiber, RF or infrared. The medium may be common or it may be shared with the possibility of requiring the use of gateways, routing devices or any other appropriate network device for carrying control commands and data signals.
Depending on the type of network medium in use in the system, the devices within the system include, within their housings, a slot that allows for the connection of a bus terminator. The bus terminator is typically an RC network that is connected to the device and serves to mechanically, as well as electrically, connect the device to the network communication line, e.g., twisted pair, coaxial, optical fiber, etc.
Thus, the system is able to communicate to devices within the system to provide intrasystem control and monitoring as well as to communicate outside the system to provide intersystem control and monitoring. Data and/or control commands are received and transmitted, various loads or control devices can be activated and switched locally and/or remotely, real time relative readings can be received and transmitted, devices can be calibrated externally in an automatic self adjusting way or via a communication link over the network.
It is important to note that both the number of and types of sensors that can be used in the system are almost endless. Examples suitable for use to control lighting and other functions in a home or office include: multiple, dual or singular occupancy and security sensing by means of passive infrared, active infrared, ultrasonic, RF, microwaves. Each may employ other single or multiple transducers such as temperature sensing, relative humidity sensing, ambient light sensing, single, dual or multiple control switching and/or dimming sensing, wish button or text scene controller sensing. Other possible sensing functions include single or multiple sensors within one device for sensing CO, smoke, security, air flow, engine monitoring, gases, water flow or level, time of day and other transducer devices.
The utility of the system of the present invention, including the individual devices that comprise it, can be illustrated using an example. Consider, for example, that in order to improve the chances of interoperability amongst different products which are developed and sold by different organizations, it is desirable to have a system which can reliably provide lighting control without restricting the building owner to devices or systems from one manufacturer. This is especially so if the system does not allow for the addition of other types of sensors that are needed to control the lighting or HVAC within an office complex. Thus, the system is very useful as it not only will function with devices that were originally designed to work within the system, but will also operate with devices developed by other organizations which utilize the same communications protocol. Note that the choice of communications protocol and physical layer for the medium is not material to the invention. Any suitable physical, link and network layer may used to implement the system of the present invention including, but not limited to the communication layers specified in the LonWorks protocol (Echelon), CEBus (Intellon), X10, CAN, BACNet, etc.
The system offers an installer a control unit, which may be a single device that comprises (1) a power supply to provide electrical power to other sensors and peripherals, (2) a system reset function, (3) load switching or dimming elements, (4) the ability to accept additional functionality permitting program instructions to be downloaded to internal nonvolatile memory, e.g., flash memory, over the network, (5) the ability to send operating mode scheduling commands, and (6) multiple processing means for implementing networking firmware in addition to application firmware previously downloaded or stored in ROM.
Moreover, given that devices generally have the ability to accept changes to their firmware via the network, it is preferable that the control units comprise a microprocessor or microcontroller which functions to execute the networking functions and the application or functionality of the system and the control unit itself. It is also preferably that the control unit is connected, via the network or directly, to a variety of sensors that are used to control various loads such as lighting and HVAC system loads. In addition, the control unit may be adapted to (1) help implement a security system inside or outside of a room or building, (2) sense sensor signals and send an alarm to a fire alarm or (3) automatically turn lights on during a fire, if so desired.
It is important to note that the invention is not limited to providing distributed sensing and control using a communication protocol such as Echelon""s LonWorks or BACNet over a twisted pair hard wired media or RF link. The invention also provides the flexibility to incorporate additional devices into the system regardless of whether one organization or many manufacture them. As long as the devices are manufactured to conform to the communication specification/protocol in use, the devices can communicate and interoperate with each other over the network.
For example, a control unit device may contain a temperature sensor to detect hot spots on the device and, in response, automatically adjust the power, switching output or dimming output capability in accordance with the temperature measured in real time within the device. Thus, the total load carrying capability of the system can be switched or dimmed based upon the current ambient temperature in a plenum or riser or system power supply, for example. Other components of such a control device include application code and device control firmware, a load switching or dimming element, low voltage inputs/outputs including: 0 to 24 mA, 100 ohm to 20 Kohm resistive and 0 to 10 V analog inputs, 0 to 30 VDC and dry contact digital inputs, 0 to 12 VDC 100 mA source and sink digital outputs, other non-protocol inputs/outputs, 0 to 10 V ballast I/O, twisted pair to PLC routing, add-on modules to provide additional dimming capability, energy monitoring device and means to optionally receive power from a source of AC power.
Another aspect of the present invention includes the ability to link a single sensor to many different actuator devices, e.g., switching or dimming elements. The ability to be linked and bound to multiple devices and functional profiles within the same node or different nodes permits a single switch to control multiple loads.
Another aspect of the present invention includes energy monitoring and the ability to monitor changes in power, current or voltage and to determine if lamps have been burned out, for example. Thus, maintenance personnel can be provided with immediate indication that lamps have degraded or have burned out. The energy monitoring function may be performed within the device itself or it may be performed by means external to the device. The data that is gathered may include the energy consumed including the power factor, voltage level, current level, etc. In addition, the feature may determine if the electrical loads have changed by using an acceptance window for power, energy, power factor, voltage and current. A determination can be made whether the levels are within appropriate specifications for a given load or if degradation has occurred over time.
To illustrate the utility of the present invention the following application scenario is presented. The system of the present invention can be used to implement each aspect of the scenario. After returning home from work, you approach the front door and the security system is disarmed using a keychain remote control. The keychain remote also triggers a series of other activities to occur within the house. If it is after dusk, the lights in the kitchen and hallway automatically turn on to light the path. The air cleaner also turns on in the bedroom to clean the air for the evening before retiring to bed.
After leaving the house for the evening, utilizing the keychain remote, the security system is armed and the house is made to appear as if someone were home, i.e., lights going on and off randomly to give the impression someone is home, etc.
Before retiring for bed for the evening, the security system is armed from a bedside remote control. The system notifies you that the garage door is not closed. After closing the garage door, the security system is armed. The system makes a check of the house and turns off all the lights.
When a service person is expected to be at the house, the system can be remotely accessed to disarm it. Some areas, however, can be left armed to protect valuables such as jewelry. Passive sensors, i.e., light, infrared, microwave, etc., can be used to detect motion and sound and send a signal to an electrical device in another part of the house to alert you of the presence of a possible intruder.
Various devices in the home can be adapted to work together to provide increased value over the individual devices by themselves. For example, in the case of fire and smoke detection, the smoke detector can determine whether it is night or day, and in response, can cause the lights to go on when it senses a fire. A signal to turn off the air handling equipment can also be sent so as to not to fan the fire. Multiple sensors working together and communicating with one another can pinpoint the fire and indicate its exact location. If the fire is near a fuel supply, the supply is turned off. The fire department and/or other specified emergency telephone numbers can be dialed.
If unsafe levels of gases, such as CO, are detected, an audible, visual or motion signal can be activated. Additional responses include turning off exhaust fans, sending emergency notification to a monitoring center or emitting one or more alarm signals within the home or building.
An example of an application, specifically the food services and restaurant industry, is to provide audio, video, lighting control and the ability to place an order right at the customer""s table in a restaurant. That is, via a user interface, e.g., display, touch screen, a customer at a restaurant can select and adjust different types of entertainment such as music, TV channels, movies, etc right at her/his table. Further, they could also set the lighting level to any desired level including different dim levels, scenes, patterns, etc. Through this interface, the customer could place their order, set their lighting level, select their entertainment, set the temperature and basically have full control over their comfort.